Transesterification Reaction Research Articles

Optimization and kinetic studies for biodiesel production from dairy waste scum oil via microwave assisted transesterification

This study presents an investigation of the optimization and kinetic aspects of the microwave (MW) heating transesterification process for converting dairy waste scum oil (DWSO) into biodiesel using lithium impregnated calcium oxide from eggshell (Li-ECaO) as a catalyst. The transesterification was done via microwave heating while varying catalyst loading (1 – 5 wt%), methanol to oil molar ratio (6 – 18:1), temperature (55 – 75⁰C), and reaction time in the range of 5 – 25 min. Response Surface Methodology (RSM) optimized the process parameters, yielding an impressive 90.5% biodiesel yield. The optimal operating conditions were determined 3 wt% catalyst loading, 18:1 methanol to oil molar ratio, a reaction temperature of 65ºC, and a reaction time of 25 minutes. A thorough kinetic analysis of the transesterification reaction for the MW heating transesterification of DWSO by Li-ECaO was performed at various temperatures (45 – 75ºC). The pseudo-first order kinetic study of the reaction revealed a moderately low activation energy of 38.86 kJ/mol and a high pre-exponential factor of 1141.27 s−1, which is consistent with previous studies. Importantly, the observed activation energy was lower than that of conventional methods, highlighting the potential of MW heating as a viable technique for future biodiesel production, and using wastes such as DWSO and eggshell could contribute to being greener and environmentally friendly.

Kinetic modeling of cationic ring-opening polymerization for the synthesis of biodegradable poly(ε-caprolactone)

Ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) is an efficient way to produce a widely used biodegradable polymer, i.e., poly(ε-caprolactone) (PCL). Compared to coordination ROP, ionic ROP receives great attentions in recent years due to mild reaction conditions and well-defined polymer microstructure. To fully exploit the potential of ionic ROP, in this work, a mathematical kinetic model for activated monomer mechanism (AMM) based cationic ROP of ε-CL was developed based on method of moments (MoM). Using the developed model, we estimated the values of the kinetic coefficients of monomer activation and monomeric units’ protonation reactions. The simulated results are found to be in good agreement with experimental data, as well as the benchmark by kinetic equation. Moreover, the simulations reveal the crucial role of transesterification reaction in molar mass distribution broadening and how the concentrations of acid and alcohol affect the monomer conversion and average molar masses of the polymer. Finally, the model was successfully extended to a newly reported system using trityl tetrafluoroborate (TrBF4) as catalyst, proving the universality of our model. This study provides deeper understanding of the cationic ROP and allows to optimize process conditions to increase the industrial sustainability of PCL-based materials.

Total Lipid Content and Fatty Acid Composition of Two Morphologically Distinct Chlorella spp. for Biodiesel Production

This study investigated the potential of two morphologically distinct Chlorella spp. to assess the total lipid content and fatty acid composition targeting biodiesel production. Due to their rapid growth, less space requirement, and zero-conflict with current food demand, green microalgae-led biodiesel production has gained a key attention as an alternative, sustainable and eco-friendly substitute for fossil fuels diminishing the increased demand for fossil fuels, fuel prices and excessive release of greenhouse gases to the atmosphere. The Chlorella spp. were isolated from Beire Lake, Colombo (Wet Zone) and Kiriibban Lake, Monaragala (Dry Zone) of Sri Lanka. They were named as BCS1 and RCS2, respectively. Semi-mass culturing of Chlorella spp. in BG-11 medium (pH=7.5-8.5) was carried out in a greenhouse providing aeration and a 12:12 light: dark photoperiod. After 4 weeks, Chlorella spp. were harvested using aluminium sulphate, employing flocculation method. Harvested biomass was oven-dried and made into a fine powder for analysis. The total lipid content (TLC) of Chlorella spp. was determined using n-hexane as the extraction solvent in a soxhlet extractor maintaining three replicates for each. Extracted lipids were dried in a rotary evaporator and TLC was calculated gravimetrically. The total lipid content of BCS1 and RCS2 was recorded as 15.67% and 18.33%, respectively. After quantification, lipids were resuspended and concentrated in 1 mL of n-hexane to convert into fatty acid methyl esters (FAMEs)/ biodiesel via a transesterification reaction. The trans-esterified lipids (FAMEs) were analysed via Gas Chromatography. The most dominant FAMEs of BCS1 were palmitic acid (C16:0), oleic acid [C18:1 cis (n9)], stearic acid (C18:0), lignoceric acid (C24:0), lauric acid (C12:0) and myristic acid (C14:0). The most dominant FAMEs of RCS2 were cis-10-pentadecenoic acid (C15:1), elaidic acid [C18:1 trans (n9)], linolelaidic acid [C18:2 trans (n6)], cis-11-eicosenoic acid [C20:1 (n9)], lignoceric acid (C24:0) and oleic acid [C18:1 cis (n9)]. A well-balanced saturated and unsaturated FAME composition is essential for the optimal biodiesel quality, herein it was found in BCS1 with 41.62% of palmitic acid and 33.38% of oleic acid. Higher percentage of oleic acid exhibits a combination of oxidative stability and low temperature properties determining the suitability of BCS1 as a biodiesel feedstock compared to RCS2. In conclusion, even though RCS2 has a higher total lipid content, BCS1 exhibits more favourable characteristics in its FAME composition as a promising feedstock for biodiesel production.
 
 Keywords: Green microalgae, Chlorella spp., Total lipid content, Lipid composition, Biodiesel

The Role of Reactive Natural Deep Eutectic Solvents in Sustainable Biocatalysis

AbstractDeep eutectic solvents (DESs) advanced in the past decade as the new generation of green and sustainable extraction and reaction media in biorefineries and in a multitude of chemical and biotechnological processes. Particularly, enzyme catalyzed reactions benefit from the specific properties of DESs, which not only ensure good substrate solubility but also enhance enzyme stability and operational efficiency. Recent studies showed that natural deep eutectic solvents (NADESs) comprising choline chloride or betaine as hydrogen bond acceptor and a large spectrum of natural compounds, such as carbohydrates, polyols carboxylic acids, as hydrogen bond donors, can have multiple functions, acting simultaneously as extraction solvent, reaction medium, source of substrate and source as catalyst. This novel approach for the utilization of multifunctional reactive natural deep eutectic solvents (R‐NADESs) in catalytic conversions opens the way to the development of greener biocatalytic and chemo‐catalytic processes, with simpler downstream processing and minimal discarded wastes, which will speed up their durable implementation in industry. This paper reviews the innovative applications of R‐NADESs in biocatalytic reactions for the synthesis of a large diversity of high value chemicals and materials, including biosurfactants, flavors, biobased building blocks and biobased polymers, with highlight on esterification, transesterification, glycerolysis, polymerization, and redox reactions.

Graphene-anchored sodium single atoms: A highly active and stable catalyst for transesterification reaction

Graphene-anchored sodium single atoms: A highly active and stable catalyst for transesterification reaction

Ultrasonic-assisted biodiesel generation from waste chicken fat utilizing a novel and reusable Ce-doped Fe2O3 nanocatalyst: Optimization by CCD, kinetics, and nano-additive on emissions and performance of a diesel engine

The present study aimed at the fabrication of an efficient nanocatalyst utilizing cerium doped on hematite (Ce-doped Fe2O3) as a highly reactive catalyst in biodiesel generation from waste chicken fat (WCF) under ultrasonication and also as nano-additive to improve diesel engine features. The surface features of Fe2O3 and Ce@Fe2O3 nanoparticles were investigated utilizing several analyses. The characterization outcomes demonstrated that the Ce element was successfully incorporated into the Fe2O3 structure. RSM-assisted experimental design was utilized to optimize effective parameters on biodiesel efficiency. According to the CCD results, the maximum biodiesel yield employing Fe2O3 and Ce-doped Fe2O3 nanocatalysts was 91.57% and 95.38%, respectively, which were obtained after 30 min of ultrasonic irradiation time. Also, various proportions of petrodiesel and biodiesel as well as adding Ce@Fe2O3 nanoparticles to the fuel blend at different torques (20–100%) were tested on diesel engine parameters. The outcomes revealed that adding biodiesel to petrodiesel diminished CO (10.02%) and UHC (6.34%). Further, increasing biodiesel content in the fuel composition enhanced BSFC (8.29%) and EGT (14.17%) parameters and declined BTE (13.37%). Besides, increasing the percentage of torque enhanced EGT and BTE and reduced BSFC. Also, adding Ce@Fe2O3 nanoparticles to biodiesel/diesel blends reduced CO, NOx, and UHC concentrations, and enhanced BTE and BSFC values. Kinetic and thermodynamic analyses reveal that the transesterification reaction is first-order and endothermic. Furthermore, the activation energy for biodiesel generation using Fe2O3 and Ce-doped Fe2O3 nanocatalysts were attained at 46.61 and 46.58 kJ/mol, respectively, which are considerable amounts. Besides, the reusability investigation showed that Ce-doped Fe2O3 nanoparticles have high stability, so that after the 7th cycle, the biodiesel yield was 87.26% (only a 7.5% decrease in efficiency). Generally, owing to unique features including high catalytic performance, considerable reusability, and high biodiesel yield, Ce-doped Fe2O3 nanoparticles are highly recommended for industrial applications.

Enzyme Mimics Based on Guanidinocalix[4]arene/ Nanodiamond Hybrid Systems with Phosphodiesterase Activity

AbstractDiamond nanoparticles are an extremely promising class of carbon‐based nanomaterials. Because of their versatility, they have an interest in a large variety of applications, however, their use in the fabrication of enzyme mimics was not previously investigated. In this study, we realized hybrid systems based on guanidinium derivatives and diamond nanoparticles by simple adsorption of the organic material on their surface. The guanidinium derivatives chosen for this study are calix[4]arenes, blocked in the cone conformation via functionalization at the lower rim with alkyl chains, and decorated with guanidinium or arginine units at the upper rim. The corresponding monofunctional counterparts were also investigated as model compounds. These materials were characterized with different experimental techniques, i. e. thermogravimetric analysis, dynamic light scattering, ζ‐potential measurements and IR/Raman spectroscopy. Their catalytic properties in the cleavage of phosphodiesters were investigated by an in‐depth kinetic analysis. The whole experimental picture points to conclude that these compounds are stably adsorbed onto the nanodiamonds surface and are active in the transesterification reaction of the RNA model compound 2‐hydroxypropyl p‐nitrophenyl phosphate in water, with a notable advantage over their catalytic performances at the same concentration in solution.

Immobilized Lipases—A Versatile Industrial Tool for Catalyzing Transesterification of Phytosterols Solubilized in Plant Oils to Produce Their Fatty Acid Esters

The conjugation of phytosterols (PSs) with fatty acids results in producing phytosterol esters (PSEs) characterized by enhanced lipophilicity and improved functional properties of major interest in food and nutraceutical applications. The use of immobilized lipases to catalyze direct transesterification reactions between PSs and plant oils to form PSEs as a green alternative to conventional chemical production methods has attracted interest during the last two decades. The low solubility of PSs in common plant oil triglycerides, typically below 3% at ambient temperatures, remains the main challenge for bringing lipase-catalyzed direct transesterification reactions of PSs and oil triglycerides to commercial scales. This study focuses on the enzymatic synthesis of PSEs starting from solubilized PSs at concentrations of up to 30% wt./wt. of oil mixtures comprising fatty acid ethyl esters (FAEEs), monoglycerides (MGs), diglycerides (DGs), and triglycerides (TGs) as a homogeneous medium for the direct transesterification reaction. The results of this study show for the first time that the addition of FAEEs into the reaction medium results in an alteration of the substrate preference of the enzyme, making MGs the favorite fatty acyl group donors for PSs amongst all other fatty acyl donors present in the reaction system. The proposed new enzymatic route allows starting with high concentrations of solubilized PSs, making the direct transesterification of oil glycerides attractive for the production of PSEs at industrial scales.

A green synthesis route of cyclohexanol via transesterification reaction intensified by reactive distillation technology

With the increasing demand of cyclohexanol in nylon industry, it is significant to develop a safe, green and economical process to produce cyclohexanol. For this purpose, a novel reactive distillation process through cyclohexyl acetate transesterification with methanol was proposed in this work. The NKC-9 catalyst was preferred to establish the reaction kinetic model based on pseudo-homogeneous model. Seven reactive distillation experiments with pilot-scale for cyclohexanol synthesis were explored to prove feasibility of reactive distillation processes and accuracy of model by comparing simulated results, which ensured the establishment of the process simulation. Furthermore, three reactive distillation processes of cyclohexanol production were designed and optimized by the sequential iterative algorithm based on minimum total annual cost. After optimization of pressure and recycled stream flow, a novel double column of reactive and pressure-swing hybrid distillation process showed the minimized total annual cost per ton product, which was 170.90 $/kg. Finally, total annual cost of transesterification, hydrolysis and hydrogenation processes were compared, and transesterification process demonstrated economic advantage. This work would provide a guidance for cyclohexanol green production by reactive distillation through cyclohexyl acetate transesterification, while a whole, economical and atomic economical reactive distillation process of cyclohexanol production could be established in the future.

Enhancing Recovery Yield of Vegetable Oil Methyl Ester for Bioresin Production: A Comparison Study Using Acid Neutralization

Vegetable oil methyl ester has promising properties for bio-based resin production due to its higher degree of unsaturation. The initial low methyl ester yield from corn oil compared to soybean and canola oils requires further investigation of the influence of neutralization at the end of the transesterification reaction. To evaluate the neutralization effect with HCl, corn, canola, and soybean oil were transesterified using NaOH at 60 °C with a 6:1 methanol–oil ratio. This research also investigated the effect of reaction times (0.5–1.5 h) with varying neutralization levels (0–100%) on the corn oil methyl ester yield. The yield of corn, canola, and soybean methyl ester was increased significantly by 16–25% through neutralization, indicating the positive impact of neutralization. The corn oil methyl ester yield ranged from 45 to 79% across different neutralization levels and reaction times. With 25% neutralization, the yield increased by 20%. On the other hand, the yield reduced by 18–24% over time when there was no neutralization. A statistical model was developed where the yield varied significantly with the acid amount, reaction time, and their interactions. The quality of the corn methyl ester was found to be within the limits of standard pure methyl ester. Overall, the effect of neutralization showed promise in increasing the yield of quality methyl ester from commercial corn oil.

Production and Characterization of Biolubricant from Cassia Sieberiana (Decandole) Seed Oil Using Transesterification Reaction

Production and Characterization of Biolubricant from Cassia Sieberiana (Decandole) Seed Oil Using Transesterification Reaction

Production of Coconut Oil Bioturbosine without Water by Using Ultrasound as a Source of Energy and Ion Exchange for Its Purification

Jet fuel production is a key element in the aviation industry’s strategy to reduce operating costs and environmental impacts. Alternatives are required, and bioturbosine obtained from biomass can replace significant amounts of jet fuel. In this investigation, the properties of the production of bioturbosine from coconut oil and mixtures of B5, B10, B20, B1OO, bottom, and jet fuel were measured according to the ASTM standards. A transesterification reaction between coconut oil and methanol was carried out using ultrasound, resulting in 99.93% conversion of triglycerides into bioturbosine at room temperature for 10 min, with a 6:1 molar ratio of methanol and oil. The catalyst concentration was 1.0 g/100 g of oil, and purification was carried out without water using an ion-exchange resin to remove impurities. The results obtained for density and viscosity were within the regulations. The temperature of the clogging point for a cold filter in the mixtures was up to −30 °C. The average caloric values of mixtures B5, B10, and B20 were 45,042, 44,546, and 43,611 MJ/Kg, respectively. In a copper corrosion test, the result for all samples was class 1A. It is expected that the results of this research may influence the use of bioturbosine in the aviation industry.

Programmable and Shape-Color Synchronous Dual-Response Wood with Thermal Stimulus.

Stimuli-responsive materials exhibit huge potential in sensors, actuators, and electronics; however, their further development for reinforcement, visualization, and biomass-incorporation remains challenging. Herein, based on the impregnation of thermochromic microcapsule (TCM)-doped dynamic covalent vitrimers, a programmable shape-color dual-responsive wood (SRW-TC) was demonstrated with robust anisotropic structures and exchangeable covalent adaptable networks. Under mild conditions, the resultant SRW-TC displays feasible shape memorability and programmability, resulting from the rigidity-flexibility shift induced by the glass-transition temperature (34.99 °C) and transesterification reaction triggered by the topology freezing transition temperature (149.62 °C). Furthermore, the obtained SRW-TC possesses satisfactory mechanical performance (tensile strength of 45.70 MPa), thermal insulation (thermal conductivity of 0.27 W/m K), anisotropic light management, and benign optical properties (transmittance of 51.73% and haze of 99.67% at 800 nm). Importantly, the incorporation of compatible TCM enables SRW-TC to visualize shape memory feasibility and rigidity/flexibility switching and respond to the external thermal stimulus through the thermal-induced shape-color synchronous dual-responsiveness, which successfully demonstrates the applications of sensing temperature, grasping objects, encrypting/decoding icon messages, and so on. The proposed facile and highly effective strategy could serve as a guideline for developing high-performance multifunctional wood composite with promising intelligent applications in performance visualization, environmental sensing, materials interactivity, information dual-encryption, local precision shape and color regulation, etc.

Analysis of a novel high-speed homogenizer technique for methyl ester production using waste cooking oil: Multi-objective optimization and energy analysis

While fossil fuels continue to be the predominant energy source, the use of renewable energy is consistently growing. Biodiesel, with its various advantages over traditional fossil fuels, stands out as a promising alternative fuel that is produced from a sustainable and abundant waste cooking oil (WCO) via a transesterification reaction (due to the low acid value of WCO) with alcohol (MeOH) and homogeneous catalyst (KOH) in a high-speed homogenizer. Biodiesel is produced in the industry using conventional mechanical stirring techniques, which are time-consuming and less efficient. It has been recently reported that high-speed homogenizers have the scale-up potential as per industrial requirements and can significantly reduce the transesterification/esterification reaction time. In the present investigation, the Taguchi technique has been applied for the design of experiments and multi-response process optimization using a composite desirability approach. The optimized values observed for yield, yield efficiency, and pour point were 99.18 ± 0.2%, 5.4 × 10–3 g/J, and − 14.9 ± 0.5 °C, respectively, at alcohol to oil molar proportion of 7:1, KOH amount of 0.5 wt%, rotor speed of 14000 rpm and 10 min of process time. The physicochemical properties of produced biodiesel were found within EN 14214 and ASTM D6751 standards limits.

Pilot scale production of biodiesel from Azolla oil via heterogeneous catalysis and diesel engine analysis: kinetic and techno-economic analysis considerations

ABSTRACT The use of Azolla pinnata oil for the production of biodiesel, coupled with the use of industrial waste dolomite as a catalyst, represents a novel approach with significant potential. This innovative process offers several key advantages, such as utilizing a non-edible feedstock, reducing waste generation, and providing an alternative to fossil fuels. This research aims to investigate the viability of creating biodiesel using Azolla pinnata oil and evaluate its technical and economic appropriateness for large-scale manufacturing. A pilot plant reactor with a 10 L biodiesel capacity carries out the transesterification reaction, using dolomite from industrial waste as a heterogeneous catalyst. The reaction was conducted for 4 h at a temperature of 70°C, and biodiesel yielded approximately 99.14%. Aspen Plus is employed to simulate and design a biodiesel plant, with the reaction kinetics derived from the pilot plant reaction and inputted into Aspen Plus. Plant optimization and economic analysis are performed using the Aspen Economic Analyzer. The biodiesel blends (Azolla 20, Azolla 40, and Azolla 60) were tested in a CI engine and compared with diesel results. Based on the engine test results, the Azolla 20 blend provides less HC (12.9%), CO (13.07%), and smoke (10%) emissions; therefore, it can serve as a better alternative to neat diesel. The primary units of the proposed plant have been designed, and the process’s economic viability was determined. It was discovered that the total capital investment needed is approximately 5.054 million USD, which will be repaid within 1.97 years of operation. This research encompasses pilot plant experiments, process simulation, engine testing, and economic analysis, demonstrating the novelty, technical feasibility, and potential socio-economic impact of this biodiesel production process.

Kinetics of Homogeneous Reaction of Potassium Methoxide Based on K2CO3 Catalyst in Transesterification of RBDPO to Biodiesel

Biodiesel production is generally catalyzed by potassium methylate or sodium methylate catalysts based on KOH and NaOH and these catalysts are still imported. The search for a cheap and effective catalyst continues to be carried out by researchers. One of the catalyst support materials currently in use involves impregnating K2CO3 with various substances, resulting in a heterogeneous catalyst. In this study, it was tried to use K2CO3 dissolved in methanol to produce a homogeneous potassium methylate catalyst. Potassium methylate-based homogeneous catalyst K2CO3-methanol is proven to have a very high function in the transesterification reaction of Refined Bleached Deodorized Palm Oil (RBDPO) into biodiesel, this is evidenced by the use of a catalyst percentage of 2% w and 30% w methanol to the weight of RBDPO resulting in an acid content in biodiesel of only 0.12% and a total glycerol of 0.124% in reaction time 3 hours, with the purity of the methyl ester in biodiesel reaching 98.80%. Meanwhile, for the calculation of homogeneous reaction kinetics, a reaction rate equation is produced where the order of the RBDPO transesterification reaction is order 2 (two) and the reaction rate constant is 0.0044.

Biodiesel production from waste cooking oil using an innovative magnetic solid acid catalyst based on Ni–Fe ferrite: RSM-BBD optimization approach

In the present study, a novel solid acid magnetic catalyst composed of nickel ferrite (NiFe2O4) and impregnated with molybdenum oxide (MoO3) was synthesized by wet method and applied in the production of biodiesel from the methyl transesterification reaction of waste cooking oil (WCO). The catalyst was characterized by the following techniques: surface acidity, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), and Vibrating Sample Magnetometry (VSM). The optimization of the variables of the methyl transesterification reaction was carried out through the Box-Behnken 24 experimental design (BBD) and the response surface methodology (RSM). The optimized experimental results led to the obtainment of a biodiesel with 95.4 % conversion to esters under the following reaction conditions: 168 °C temperature, 30:1 methanol:WCO molar ratio, 10 wt% catalyst amount, and 1 h reaction time. The mathematical model developed showed an error of less than 5 % between the observed and predicted values. In addition, the catalyst showed bifunctional character (catalytic and magnetic) and high stability after seven reaction cycles, with conversion to esters above 90.3 %, as well as high versatility in the presence of various raw materials, indicating its high potential for development and application.

Optimization and kinetic study of biodiesel production from Jatropha curcas oil in supercritical methanol environment using ZnO/γ-Al2O3 catalyst

AbstractIn this study, the conversion of crude Jatropha curcas oil into biodiesel through transesterification was investigated in the presence of heterogeneous solid catalysts under supercritical methanol environment. The principal impetuses catalyzing the expansion in optimal biodiesel production are primarily attributed to the increasing demand for sustainable energy sources, the availability of raw materials, and innovations in production methodologies. To maintain the optimization, 6 wt% and 10 wt% of zinc oxide (ZnO) were incorporated into gamma-alumina (γ-Al2O3) through a wet impregnation method followed by calcination at 900 °C. Furthermore, the study examined the effect of alcohol/oil molar ratio, reaction temperature, and reaction time on the process to achieve maximum biodiesel production. The study revealed that a catalyst consisting of 10 wt% ZnO on γ-Al2O3 exhibited exceptional performance with a biodiesel yield of 95.64% under the reaction conditions of a molar ratio of 1:40 oil to methanol, a temperature of 300 °C, a pressure of 9 MPa, and a residence time of 3 min compared to the yield of 100% under same condition at residence time of 9 min. After thorough investigation, the kinetics of the catalytic transesterification reaction were elucidated, and suitable kinetic parameters were proposed.

Design of anti-saponification Ca-based catalyst with porous-shell structure from crustacean waste for biodiesel production

The rapid development of the biodiesel industry is of significant importance for achieving carbon emission reduction in the transportation sector. However, the presence of trace amounts of water in the feedstock during biodiesel synthesis may lead to severe saponification reactions, thereby reducing the yield of fatty acid methyl esters. In this study, based on our exploration of the characteristic of porous carbon to absorb moisture from the environment, we synthesized a CaO catalyst with porous carbon coating via discarded shrimp shell biomass. Because the carbonization temperature of organic matter in shrimp shells is lower than the decomposition temperature of CaCO3, the CO2 generated during pyrolysis can erode the pyrolytic carbon and form porous structure. The mesoporous carbon shell facilitates the diffusion of oil and methanol molecules while adsorbing moisture in the alcohol phase. This structure effectively minimizes the interaction between CaO and water, thereby suppressing saponification reactions and ensuring the smooth progression of the desired transesterification reaction. Through a series of physicochemical characterizations, the structure and water absorption performance of the catalyst were confirmed. The as-prepared CaO@PC-900 catalyst demonstrated the ability to maintain a biodiesel yield of over 85% in a reaction system with a water content of 3%, significantly surpassing the performance of commercial CaO and previously reported Ca-based solid bases. This work provides a new approach to the design of anti-saponification transesterification catalysts, while also offering a novel pathway for the synthesis of porous carbon from discarded crustacean biomass.

Biodiesel production performance estimation from simple viscosity measurements

In a biodiesel production industry a quick monitorization of the reaction extent achieved in the process it is important. The usual way to determine the reaction yield is to analyze the FAME content in the biodiesel reaction product. Analytic methods used, mainly gas chromatography, require previous sample treatment or tedious calibrations. Recently, less complicated analytic methods (nuclear magnetic resonance, infrared spectrophotometry) have been developed but they require costly equipment and analysis. The aim of this paper is to develop a cheap and fast method in order to quantify the FAME content in the reaction mixture from simple dynamic viscosity measurements and then the transesterification reaction yield. Therefore, experimentally obtained correlations from biodiesel proceeding of several oil feedstocks are presented in order to estimate the biodiesel FAME content from its dynamic viscosity, a fast determination parameter.